\input pstricks.tex
\input pst-plot.tex
\input pst-node.tex
\nopagenumbers
\vrule height 15em width 0pt
$
\psset{unit=1.3em,linewidth=0.4pt}
%\everypsbox{\scriptstyle}
\psaxes[labels=none,ticks=none]{->}(0,0)(-2,-1)(9.5,6.5)
\psset{labelsep=0.5ex}
\Rput[l](9.5,0){x}
\Rput[l](0,6){y}
\psset{linewidth=0.8pt}
\pcline(0,0)(7,5)
\Aput{r}
\pcline(0,0)(7,0)
\Bput{a}
\pcline(7,0)(7,5)
\Bput{b}
\Rput[tr](0,0){O}
\rput[bl](7,5){M(a+bi)}
\uput{1}[18](0,0){\varphi}
$
\bye
